(function anonymous(name, age, _callback) {//_callback最后的回调
    var _x = this._x;//数组
    var _counter = 3;//长度
    var _done = (function () {
        _callback();
    });
    _x.forEach((fn)=>{
        fn(name, age, function () {
            if (--_counter === 0) _done();
        });
    });
})